Soil sampling machine



June 30, 1953 J. A. HARDMAN 2,643,858

SOIL SAMPLING MACHINE Filed June 14, 1948 s Sheets- Sheet 1 FIG. I..

Snvemor: JAMES A. HAR OMAN,

June 30, 1953 J. A. HARDMAN 2,643,858

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June 30, 1953 J. A. HARDMAN son. SAMPLING MACHINE 8 Sheets-Sheet 5 Filed June 14, 1948 FIG.

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June 30, 1953 J. A. HARDMAN 2,543,858

SOIL SAMPLING MACHINE Filed June 14. 1 948 8 Sheets-Sheet 6 FIG. l7. FIG. I8.

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80 JAMES A. HARDMAN,

June 30, 1953 J. A. HARDMAN 2,643,858

son. SAMPLING MACHINE Filed June 14, 1948 8- Sheets-Sheet '7 FIG. 26.

3nvemor:

Q JAMES A. HARDMAN 1 a tttnegg J. A. HARDMAN SOIL SAMPLING MACHINE June 30, 1953 8 Sheets-Sheet 8 Filed June 14. 1948 Patented June 30, 1 953 SOIL SAMPLING MACHINE James A. Hardman, Logan, Utah, assignor to Utah Scientific Research Foundation, Logan, Utah, a corporation of Utah Application J use 14, 1948, Serial No. 32,847

19 Claims. 1

This invention relates to machines for securing soil samples in the form of cores revealing soil characteristics to given depths below the surface.

Among the objects of the invention are:

To enable the taking by machine of undis turbed core samples of soil to appropriate depths from the surface;

To provide a soil sampling machine which is readily transportable from location to location and which may be easily operated by only one person;

To provide, in such a machine, for the taking of cores of different diameters as found desirable, this being accomplished by the provision for the simple and convenient changing of the core sample tubing on location;

To further provide, in such a machine, for the taking of cores at any angle from the horizontal to the vertical; for different speeds of operation; for automatically regulating driving pressure or thrust on the drill tubes, variably thereof, substantially in proportion to the soil resistance; for visually and audibly indicating core compaction or other undesirable phenomena due to too great resistance of the soil to drilling; for taking an undisturbed core sample in successive stages where the nature of the soil leads to compaction or other undesirable phenomena before a complete sample is obtained; and for safeguarding the machine against damage if the drill tube jams during a drilling operation.

In accordance with the invention I preferably mount drilling mechanism upon a slideway pivotally mounted upon and extending longitudinally with a chassis which is provided with road Wheels and arranged as a trailer for attachment to an automotive vehicle. The slideway and drilling mechanism are arranged to be elevated or tilted from a substantially horizontal traveling position to any desired drilling angle, an engine being advantageously provided on the chassis for motivating the elevating means and for driving the drilling mechanism through a manuallyshiftable speed transmission equipped with reverse. The drilling mechanism is advantageously arranged on the slideway for sliding movement into a position substantially counterbalancing the engine and transmission so that the hitching of In preferred embodiments the drilling mechanism includes a drill tube assembly having a rotatable, external drill tube, a core-receiving or soil sample tube, and a control tube for actuating core-parting and core-supporting means which advantageously take the form of extensible, corekeeper fingers. 'A special drive arrangement, taking power from the transmission, serves not only to rotate the external drill tube, but also to exert longitudinal thrust, either in the direction of drilling during a drilling operation or oppositely, at the completion of any drilling operation, when it is desired to remove the external drill tube from the soil. During the drilling operation, the force of such longitudinal thrust is automatically regulated by the torque necessary to rotate the drill tube against the resistance of the soil.

The core-receiving or soil sample tube is arranged to be removed from the external drill tube while the latter is still in the ground, thereby maintaining the drill hole open for subsequent drilling stages. Advantageously such soil sample tube is longitudinally split so it can be easily opened for core removal.

Axial drilling pressures are indicated during the drilling operation by resilient pressure-reacting means preferably capping the core-receiving tubes, so that conditions which would disturb the core sample, such as compaction, may be relieved by the operator before the sample is damaged.

A core arrangement is advantageously integrated With the slideway for use in shifting the core-receiving tubes from the external drill tubev Fig. 1 represents a side elevation of the soil I sampling machine inapproximately its traveling position, the drilling mechanism being raised somewhat to facilitate illustration;

Fig. 2, a similar View but illustrating the machine elevated to a vertical drilling position;

Fig. 3, a top planof the drilling position of Fig. 2;

Fig. l, a rear elevation of the drilling position of Fig. 2; I

Fig. 5, a detail elevation of mechanism for raising the drill tube assembly to operative position, the view illustrating the mechanism in the travelling position of Fig. 1;

Fig. 6, an enlarged transverse section taken on the line 6-6 of Fig. 1 and illustrating thrust mechanism associated with the driving head of the drill tube assembly;

Fig. '7, a left-hand elevation of the mechanism of Fig. 6;

Fig. 8, a top plan of the mechanism of Fig. 6;

Fig. 9, an enlarged section taken on the line 99 of Fig. 6;

Fig. 10, a detail elevation of the drill tube assembly;

Fig. 11, an enlarged transverse section taken on the line li-H of Fig. 10;

Fig. 12, a broken longitudinal diametric section taken on the line l2li2 of Fig. 11;

Fig. 13, an enlarged transverse section taken on the line i3l3 of Fig. 10;

Fig. 14, an enlarged, fragmentary, longitudinal section taken with reference to the line i4l4 in Fig. 13, and showing the drill-bit end of the drill assembly as it appears with core-keeper fingers retracted before and during a drilling operation;

Fig. 14a, a fragmentary portion of Fig. 14 showing an alternative position of the lifting fingers where the latter are lowered to engage the earth core for the lifting operation;

Fig. 15, a similar viev, but showing only the outer drive tube in section, the fingers being extended as they are when a soil core is being removed;

Fig. 16, a transverse section I6IE of Fig. 15;

Fig. 17, an enlarged detail elevation of the taken on the line pressure-indicating and drill-tube control assembly as viewed in Fig. 4-;

Fig. 18, a top plan of the same;

Fig. 19, a fragmentary detail section taken on the line |il!9 of Fig. 18;

Fig. 20, an elevation taken from the right in Fig. 19;

Fig. 21, an elevation from the left with reference to Figs. 17 and 18, and showing the position which corresponds to the retracted position of the fingers in Fig. 14;

Fig. 22, a similar view but showing the position which corresponds to the extended position of the fingers in Fig. 15;

Fig. 23, an enlarged fragmentary detail elevation taken from the line 2323 of Fig. 4;

Fig. 24, a section taken on the line 24-24 of Fig. 23;

Fig. 25, a detail elevation of the special chain and sprocket drive arrangement for the drilling mechanism;

Fig. 26, an enlarged elevation, partly in section, of the drill tube assembly and associated drive mechanism as viewed in Fig. 4, part of the length of the drill tube assembly being broken out, and the pressure-indicating and control assembly being illustrated in detail;

Fig. 2'7, a constitution diagram showing interrelationship of the several parts of the machine;

Fig. 28, a detail elevation of an alternative form of elevating arrangement for the drilling mechanism; and

Fig. 29, a top plan view of same showing a position of the hydraulic actuating and control system.

Referring now to the drawings: the soil sampling mechanism is shown mounted on a chassis comprising an open structural framework, see Fig. 3, supported on a pair of road Wheels 3| and provided with a tongue 32 terminating in a trailer hitch 33 of any suitable type. The Wheels 3i are advantageously secured in well-known manner to an axle disposed at or well to the rear of the chassis. Protective fenders 3d are provided in customary fashion, the same being, however, prelerably flat-topped and equipped with racks to receive and carry extra sampling tubes or collected soil samples.

Positioning Mechanism The fenders 34 are, in this instance, suitably reinforced structurally to support the weight of the drilling mechanism hereinafter described, the latter being slidably carried by a pair of tubular rails 35 affixed to a shaft 3l', Fig. 3, which is journaled at its opposite ends in bearings 38 mounted on the fenders at the rear thereof, as illustrated.

The rails 36 are secured together in properly spaced relationship by means of transverse tie pieces 39, offset from the rails proper by respective sets of hangers 40, see especially Figs. 5 and 6. As so arranged, the rails 35 form a slideway upon which the drilling mechanism is slidably mounted by means of a carriage 4! having elongate shoes 42 and 43 fitted over the respective rails.

The slideway formed by the rails 36 and associated structure as above-described is rigidly affixed to the shaft 31 by means of bracket clamps 45, Fig. 3, and is arranged to be elevated or tilted from the riding position shown approximately in Fig. 1, to the vertical position shown in Fig. 2, or somewhat therebeyond, by means of a sector gear 45 and drive pinion 46, see especially Figs. 3 and 5. For this purpose, the sector gear is affixed to the shaft 37 and the drive pinion to a shaft 47 arranged to be driven at reduced speed by an engine 48. The power passes from engine 48 to a manually-operable speed transmission 49,

' preferably by means'of a double V-belt drive 50,

and from the transmission 49 to a countershait 5! by means of a chain drive 52 which includes a large bull sprocket 53 afiixed to the countershaft. From the countershaft 51, which is concentrically and rotatably mounted on the shaft 37, a small drive sprocket 54 transmits the power to shaft Ill and pinion 46 by means of a chain drive 55. A clutch 56, manually operable by means of the handle 51, Fig. 4, is arranged to connect the small drive sprocket 54 with the countershaft 5| at such times as the operator desires to raise or lower the slideway and drilling mechanism, it being understood that the transmission 49 transmits power either in forward or reverse.

Accordingly, the slideway and drilling mechanism may be positioned for operation at any angle between approximately the horizontal and approximately the vertical, as desired by the operator, the journaling of the pivot shaft 31 at the rear of the fenders 34 providing clearance for swinging the slideway and the thereby carried drilling mechanism somewhat forwardly of the vertical, about 15 degrees, if desired.

Alternative mechanism for raising and lowering the slideway and drilling mechanism is illustrated in Figs. 28 and 29, and will be described hereinafter.

In the traveling position. the forward end of the slideway and drilling mechanism rests upon a post 59 rising from the frame or chassis 30. For clarity of illustration, however, the slideway and drilling mechanism are shown raised to the exact horizontal in Fig. 1. It should be noted that, in the traveling position, the weight concentrated forwardly of the road Wheels 3| is such that it would be extremely difficult if not impossible for one man to lift the tongue 32 for the purpose of hitching it to an automotive vehicle. However, as arranged in accordance with the invention, the drilling mechanism maybe slid along the slideway toward the rear of the trailer until the weight of the engine 48 and associated equipment is substantially counterbalanced. The tongue 32 may then be easily lifted into hitch position, it being possible for one man to carry out the entire hitching operation by himself.

The drilling mechanism comprises a drill tube assembly, drive mechanism therefor, and compaction indicating and regulatingmeans.

The drill tube assembly The drill tube assembly is arranged'to bore into the soil to a desired depth for'obtaining an undisturbed core sample. To this end it comprises an outer drill tube '66, (Figs. to 14) whose lower end is internally threaded for the reception of a cutter head 6!, and whose upper end is flanged as at Gila. for attachment to the drive mechanism, see Figs. 9 and 26. Fitting snugly but rotatably within the drill tube 60'is a concentric control tube 62 which passes com pletely through the drive housing 63 and is capped by pressure indicating and applying means hereinafter described. Fitting snugly within the control tube is a diametrically split, relatively thin-walled soil sample tube '64, separable into two longitudinal sections for core removal.

The split soil sample tube 64 advantageously extends somewhat beyond the control tube 62 at the upper or control end of the drill tube assembly as shown, Figs. 10, 12 and 26, and terminates sufficiently short of the cutter head 6| at the opposite lower or drill end of the drill tube assembly, see Fig. 14, to permit passage of resilient soil-keeper fingers for core parting and removal, as described hereinafter.

At this lower end, each longitudinal half-section of the split tube 64 has affixed to its outer face a marginal collar half-section which, in the installed position, is a component of a collar65 that completely encircles the outer lower margin of the split tube 64, see Fig. 16. This collar 65 is longitudinally slotted about its inner circumference to provide a plurality of slots 66 circumferentially of the lower end of the split tube, which serve to receive and permit slidable passage therethrough of arcuate, resilient, corekeeper fingers 67. Such core-keeper'fingers are preferably arcuately bent and tempered short lengths of strip steel of suitable width which slide in the slots 66 when the fingers are extended.

The control tube 62 is deeply and narrowly slotted at its upper end, preferably diametrically as at 68, Fig. 10, and receives a locking ring 69, Fig. 26, which clamps it tightly to the split soil sample tube 64. The opposite lower end of such control tube is more widely slotted, also preferably diametrically as at 16, Fig. 15, for the reception of respective tongues ll which are integral with and extend radially outwardly from the respective longitudinal half-sections of the split tube 64. Such tongues H extend into the collar 65, and preferably have an outward projection from the respective half-sections commensurate with that of said collar.

The length ofthe control tube 621s .such th-at, when clamped tothe split tube64 forthedrilling operation as shown in Fig. .26, its lowerend terminates short of the collar 65, see Fig. .14, by a distance equal to the desired extension of. the core-keeper fingers 61 within the soil sample tube as claws in a so-called crow foot action hereinafter described (see Fig. 15 for the extended position of the fingers acting as claws). The slots 10 of the control tube and their received tongues II are of such length as to afford. positive engagement at all times, whereby the split soil sample tube and the control tube may be turned as a unit without subjecting the former to undue stress and strains.

It should be noted that the collar 65 Figs. lfl, 14A, 15 and 16, of the split soil sample tube64 rests upon a circumferential shoulder l2. formed internally of the cutter head 6|, whereby the tubes disposed internally of the outer drill tube are supp rted and retained therein.

The cutter head 6| terminates in acircumferential cutting edge Bla, Figs. 14 and 15, and is provided with externally projecting, soil-cutting lugs 13 directed to bite into the soil when the drill tube 66 is rotated. Trowel lugs 14, Fig. 26, project externally from the lower portion of the drill tube 66 in staggered relationship with the lugs 13, these lugs being diagonally disposed and directed to provide open passage for limited elevation of the particles of earth cut in the drilling operation by the soil-cutting lugs.

The operative action of the lugs 14 can best be explained by reference to Fig. 26. In this figure it is to be observed that each lug '14 projects radially from the cylindrical face of outer drill tube 66. Thus the lugs-during rotation ofthe drill tube generate an annular space between the cylindrical surface of the drill tube and the cylindrical face of each lug. Naturally the radial upper surface of each lug l6 intersects the cylindrical face thereof and forms a cutting lip 14a at the lower end, an ascending face portion 14b adjacent the cutting lip, and a follower portion extending away from the ascending portion. The function of the lug 14 by means of the ascending portion Mb is to have the tendency to slightly elevate the particles loosened by the lip Ma and finally, by means of the portion Me, which latter is substantially transverse to the rotative axis of the tube-66, to plaster or trowel at least a portion of theelevated particles upwardly against the lower 'portion of the material inthe annular space defined by the rotation of the lug 1-4.

Mounting of the drill tube assembly, above-described, for sliding movement on the slideway formed by the rails 36, is accomplished by means of a drive head 63, through which the upper ends of the control tube 62 and the split soil sampling tube 64 pass, and further, by means of a tail plate 75, carrying a pair of guide rollers 16, through which the lower end of the external drill tube 60 passes.

The drivehead 63 rests in and is advantageously bolted to the carriage tl as shown in Figs. 6 and 8. The tail plate 15 is secured across the lower end of the slideway in any suitable manner, as by weldingto the rails 36, see Figs. 1, 2, and s.

Each guide roller 16 is snugly confined forrotation'between a top plate 11 and a bottom'plate 18, Figs. 23 and 24, by means ofthredcircumferentially contacting posts made up; ofjstuds 19, which secure the two plates together, and

spacing sleeves 80. These posts act ascleaners for the roller. The bottom plate T8 is extended as a bracket for securing the assembly to the tail plate. p e

The rotative axes of the guide rollers 16 are parallel with the slideway and drill tubes, so that the rollers themselves are transversely disposed and rotate with the drill tube 60. To prevent scoring of the drill tube, the circumferential edges of the guide rollers 76 are chamfered as shown.

The drive mechanism The external drill tube 69 is arranged to be constantly rotated during the drilling operation by means of a traveling-drive connection deriving power from the engine 48 through the transmission 49. This drive connection is so made as to exert a downward pressure or thrust on the drill tube assembly during the drilling operation, such thrust being automatically regulated in accordance with the character of the soil.

Within the housing of drive head 63, a sleeve Bl, Fig. 9, concentric with and encircling the control tube 62, is rotatably mounted by means of ball bearings 82. The sleeve Bl carries a bevel gear 83 rigidly affixed thereto. Within an oiiset portion 63a of the housing of drive head 53, a shaft 84 is journaled by tapered roller bearings 85. The inner end of such shaft rigidly carries a pinion 86, which meshes with and serves to drive the bevel gear 83. Afiixed to the outer end of such shaft 84 is a drum 37 having a sprocket wheel portion 88 through which power is transmitted. The sleeve 8| makes connection with the flange 60a of drill tube 6!! through an intermediate ring 89 which retains oil packing 90 in place. Similar oil packing 9c is retained at the opposite end of the sleeve by means of a seal ring 9|, Figs. 6 and 8, it being understood that the housing of drive head 63 is sealed so that themechanism will rotate in a bath of oil. As thus arranged, the exterior drill tube 58 and the cutting head 6!, carried thereby, are rotated by means of the sprocket portion 88 of drum ill.

For transmitting rotary motion from the engine-driven transmission as to the sprocket portion 88 of drum 81, a special chain and sprocket wheel drive arrangement is employed, the power passing to such special drive arrangement by way of the countershaft 51. A sprocket Wheel 95, Figs. 3 and 4, fixed to countershaft 5|, has drive connection with a sprocket wheel 96 by means of a chain 91. Sprocket 96 isainxed to one end of a countershaft 93 which passes through and is journaled in the lowerend of one of the rails 36. Afilxed to the other end of. the countershaft 98 is a sprocket wheel 99 which comprises part of the aforementioned special drive arrangement.

The special drive arrangement allows longitudinal movement of the drill tube assembly and directly associated drive mechanism, and, in addition to rotating the sprocket portion 88 of drum 81 and therewith the drill tube Gil, eifects longitudinal thrust which produces the said longitudinal movement. When operating in forward or drilling direction, the force of this longitudinal thrust is automatically regulated by the resistance offered the cutter head 6| by the soil through which it cuts.

In addition to the sprocket 99, which acts as a drive, the special drive arrangement includes the driven sprocket portion 88 of drum 8?, and further comprises an idler sprocket wheel lot),

Fig. 4, mounted for free rotation at the upper end of the slideway 36 on a-stub shaft lfll which is carried by a bracket support H12 extending from a crosspiece H13 at the end of the slideway. An elongate chain loop I04, see particularly Fig. 25, passes around the drive sprocket 99 and the idler sprocket lll'll, encompassing the driven sprocket portion 88 of drum 87, as illustrated. A pair of idler guide sprockets I05, freely journaled in bracket arms I06, Fig. l, maintains the chain in proper engagement with the driven sprocket portion 88 during the travel thereof longitudinally along its reach of the chain, in the manner indicated by dotted lines.

In operation, the varying resistance of the soil to cutting by. the cutter head El creates a correspondingly varying tension or pull on the said reach of the chain I04 in the direction indicated by the arrow in Fig. 25, which proportionately moves the driven sprocket portion 88, the drive head 63, and the drill tube assembly in that direction while the drill tube 60 and the cutter head 6| are rotating.

A friction brake I01, normally operable by a handle I 68, see especially Figs. '7 and *8, is operable on the drum 8? for providing any desired degree of resistance to rotation of the sprocket portion 88, either to augment the natural soil resistance in a drilling operation if desired for any reason, or to facilitate removal of the drill tube assembly from the soil following any drilling operation, it being understood that throwing the transmission 39 into reverse drives the chain 04 in reverse and changes the direction of longitudinal movement of the drilling mechanism.

Indicating and control means During the drilling operation, if the cutter head 6!, Fig. 14, encounters too much resistance in the soil, the tendency is to churn the core sample istence of those conditions, so the operator may take necessary corrective steps, for example, remove the core sample to the extent already taken and continue the drilling in successive stages to produce a discontinuous yet consecutive and thus, representative core sample.

Removably mounted upon the drive head 63, Fig. 26, is an arrangement comprising a base plate H2 having a control circular opening, through which extend the upper ends of the control tube 62 and split soil sample tube 64. Rising from such base plate and extending over the circular opening therein is a hinged, tube-capping assembly, which, in conjunction with the clamping ring 69 and associated structure, reacts to upward pressure of the soil sample tube M and control tube 62 and affords indication, as well as enabling manual feel and regulation of the longitudinal drilling pressure. The manual feel of such drilling pressure gives an indication of the thrust tension on the chain drive I0 1.

Such tube-capping assembly includes a lever assembly, consisting of a lever or cross-arm H3 hinged by means of a link H4 to a standard H5 fixed to the base plate H2. The cross-arm H3 carries pendant therefrom, a cap H5 arranged to fit over the upper end of the split soil sample tube 64 and to normally rest upon the upper end of the control tube 62 and upon the clamping ring 69. The cap H5 is cupped sufliciently deeply to allow clearance for a downward stroke,

over the soil sample tube 64 equal in length to the extension of the core-keeper fingers 67 within the tube when extended as claws in the afore" mentioned crowfoot action thereof, it being understood that telescoping of the control tube 62 downwardly relative to the sample tube 64 to effect thesaid crowfoot action of the corekeeper fingers is accomplished manually by means of the cap H6. As here illustrated, see Figs. 18 and 21, the cap I I constitutes virtually an axial-pressure reacting means and is made up of a ring H611 and a deeply bent crosspiece I It?) of strap metal, the latter being pivotally secured to the cross-arm H3, intermediate its length, by means of ears I I I aflixed to the cross piece I Itb as by welding, see Figs. 22 and 26.

The cross-arm H3 is extended at its free end, as I'I3a, to form a manually-operable handle for exerting downward pressure on the cap II6. Suchhandle normally engages a catch HS, Figs. 19 and 20, of a pressure control standard IIFl, the catch being urged downwardly by a spring I20 whose tension or bias can be regulated by a thumb-screw I2I'. The pressure-control standard H9 is fixed to the base plate H2, and a hand-screw I22 enables the catch mechanism to be raised or lowered thereon. Such mechanism provides, in eifect, a resilient, pressurereacting, latching assembly for the handle IIBa.

The clamping ring 69 cooperates with the pressure-control standard as an indicator of compaction or of other undue pressure-producing phenomena such as too Wet soil. For this purpose it is provided with diametrically opposite pins I23 which extend outwardly and engage respective risers I24 that rise rigidly from and are fixed to the base plate H2. The risers are stepped, asillustrated, see particularly Figs. 21

and 22, and during normal drilling operationsthe pins I23 rest on the lowermost steps thereof, see Fig. 21. A tendency of the pins I23 to climb to the next higher step or the actual climb thereof tosuch next higher step, indicates undue resistance to the drilling operation and an abnormal condition, such, as compaction, which ordinarily must be corrected. It should be noted that the risers I2 4 absorb the downward pressure normally exerted on the handle IIIia Core retrieving mechanism Upon the completion of'any drilling operation or of any one of successive stages of a drilling operation, the core sample is prepared for removal by bringing into play the crowfoot action of the core-keeper fingers 5?, as heretofore mentioned. For this purpose, the clamping ring 69 is loosened by means of the hand-screw S9-I, and is rotated so as to disengage the pins I23 from the stepped risers I 25. If necessarythe cap I I6 may be raised to give clearance by loosening the hand-screw I22 of the catch mechanism I I8 and raising such mechanism on its standard H9. Thereupon, downward pressure by the operator on. the handle 3d telescopes the control tube 62 downwardly with respect to the split soil sample tube 64, see Fig. 22, forcing the greater length of the core-keeper fingers 6? through the slots 68 of collar 6'5, see Figs. 15 and 16, out from normal withdrawn position and into extended core-parting and core-supporting position, all as illustrated. The core sample is nowready for removal.

As illustrated in Figs. 2, 3, and 4, an extensible mast I26 is slidably fitted within the hollow of one of the rails 36 for upward extension sufficient to give clearance for the removal of the sample-containing tubes. Such mast is normally maintained retracted by a set screw I27, and is arranged for fixed positioning at the proper heightby alatch I28 cooperating with a keeper I29 on the-mast. The mast I26 carries an arm I30 fitted with apulley 53! at its.

outward terminusadapted to be positioned directly over the drill tube assembly. By passing a line over the pulley and attaching one end to the clamping collar 69, which meanwhile has been retightened securely, the operator has in effect a cranefor pulling the control tube 62 and sample tube 56,- as a unit, up out of the external drill tube 60.

It should be noted that, during the hoisting operation, the core-keeper fingers t7 adequately support the core sample. Their curved, resilient formation cause binding of the ends retained within the slots 66, and prevent their being forced out by the Weight of the core sample. g

Upon removal, the tube assembly is placed in one of the racks. 35,.andthe split soil sample tube 64 is withdrawn from the control tube $2 and opened to release the core sample.

During the removal of the core sample as aboveexplained, the external drill tube remains in the position assumed in the drilling operation, thereby protecting'the walls of the bore against caving. This is important in instances where the drilling operation is carried out in successive stages to produce a core made of Sequential segments. 7

Operation The operation of the, machine has been largely explained heretofore in connection with the description of the component parts. Nevertheless, to recapitulate briefly: following the transportation of the machine in its traveling position. to the drilling site, the engine 48 is started and the transmission 49 shifted from neutral into low forward speed. The clutch 5? is thrown into engagement by the handle 56 for a length of time sufficient to raise the drilling mechanism from traveling .,to. a desired drilling position. Thereupon, the transmission is shifted to the desired higher forward speed for drilling.

As .afore-explained, the special drive arrangement acting on thesprocket portion 88 of drum 8? by means of the elongate drive chain its not only effects rotation of the external drill tube 60, but also automatically determines the longitudinal thrust, or rate of descent of the drill tube assembly in the soil, in accordance with the character of the soil as expressed by resistance to the drilling operation.

Compaction or other undesirable pressureproducing. phenomena during the drilling operationv requiring attention to prevent damage to the core sample is indicated visually by rising 11 of the pins 523 of locking ring 89 on the stepped risers I24 and audibly by the click produced in change of position of such pins from respective lower to respective higher steps. Furthermore, a direct measure of the extent of drilling pressure necessary to overcome undue resistance of the soil to the drilling operation is aflorded the operator by the judicious manual application of pressure on the handle I I3a.

Damage to the machine by the encountering of rocks or excessively hard strata during the drilling operation is prevented not only by the operators attention to the compaction-indicating mechanism, but also by the fact that the V-belt drive 50 from engine to transmission acts as a safety, slipping when it is impossible to turn the drill tube 60 and cutter head I5 I Upon completion of the drilling operation or of any separate sequential stage thereof, the core sample is parted from its natural rooting by the action of the core-keeper fingers 61, as heretofore explained, and is removed with the tubes 62 and 6G by the use of the crane provided for the purpose. 7

Removal of the external drill tube 60 from the soil after a complete core sample has been obtained is accomplished by shifting the transmission 49 into reverse and. if necessary, applying the brake It! tothe drum 8? of the drill drive mechanism whereby required tension is applied to the left-hand reach of the chain I84 in Fig. 25 and the drill mechanism is elevated on the slideway 36.

Return of the slideway 36 and drilling mechanism to traveling position is accomplished by throwing the clutch 51 into engagement while the transmission is operating in reverse.

Hydraulic elevating mechanism An alternative form of elevating mechanism for the slideway and drilling mechanism is illustrated in Figs. 28 and 29. There a hydraulicallyoperated plunger and cylinder assembly I35 is pivoted at !35 to the trailer chassis 30. The plunger rod I 3'! terminates in a cross-arm I38 which is journaled in spaced ears I39 depending from a transverse plate I48 joining the rails 36 of the slideway.

A pump I4I for fluid, preferably oil, is arranged to be driven directly from the engine 43 by means of a drive arrangement I42. The pump MI is connected to the cylinder of the assembly I35 by means of pipes I43, and includes a suitably valved circulatory system (not shown) for permitting either free circulation of the fluid or supply thereof to the said cylinder, with corresponding return, through the pipes I43.

Raising or lowering of the slideway and associated drillin mechanism is accomplished by proper manipulation of the valve means of said circulatory system.

The preferred specific embodiment of the invention here illustrated and described embodies all the features of the present invention in a completely integrated machine. Yet many of the novel features may be utilized separately to advantage in connection with other structural combinations.

Whereas this invention is here illustrated and described with respect to a preferred specific embodiment thereof, it is to be understood that various changes may be made in said embodiment and that the generic inventive concepts involved may be embodied in various difierent forms by those skilled in the art, without departing from the invention as defined by the following claims.

What is claimed is:

1. A coil sampling machine, comprising a rotatable drill tube; means for rotating said drill tube; a removable soil sample tube disposed concentrically within said drill tube for receiving core samples cut by said drill tube; a cutter head removably secured to the drill end of said drill tube; soil cutting lugs fixed to the lower end of said cutter head; trowel lugs projecting radially from said cutter head and located in operative proximity to said soil cutting lugs; each of said trowel lugs having a substantially cylindrical face and a radial face portion intersecting said cylindrical face, said radial face portion including a cutting lip at the lower end thereof, an ascending face portion adjacent said cutting lip, and a follower portion extending from said ascending portion, said follower portion being substantially normal to the rotative axis of said cutter head.

2. In a soil sampling machine having a rotatable drill tube, means for rotating said'drill tube,

and a removable soil sample tube disposed con-' centrically within said drill tube for receiving core samples cut by said drill tube, axial-pressure reactin means operatively connected with the soil sample tube for indicating the occurrence of core compaction, said axial-pressure reacting means comprising a reaction member disposed around the outside of the upper end of the soil sample tube; a lever assembly bearing on said reaction member; bias means associated with said lever assembly so the force of the bias means is exerted upon said lever assembly; and latching means disposed to selectively control the extent of the force exerted by said bias means.

3. A soil sampling vehicle, comprising a rotatable drill tube; a removable soil sample tube disposed concentrically within said drill tube for receiving soil samples cut by said drill tube; a driving mechanism for said drill tube, which includes a gear head disposed to impart rotary motion and axial unilateral motion to the drill tube; an endless flexible connector intergeared with said gear head; a longitudinal slideway having fixed guide idlers for said flexible connector at both ends thereof; pivot means securing the slideway to the vehicle intermediate the fixed guide idlers for tilting to various drilling positions; means slidably mounting the drill tube assembly on the slideway; and soil-sample retrieving means associated with said slideway.

4. The combination recited in claim 3, wherein the longitudinal slideway is composed of two guide rails substantially parallel to each other, said driving mechanism being mounted on one of said guide rails substantially in the longitudinal plane of that guide rail; and wherein said soil-sample retrieving means includes a crane structure mounted on the other guide rail, the crane structure having a cross-arm overhanging said soil-sample tube.

5. A soil sampling machine, comprising a rotatable drill tube having a drive head affixed thereto; a longitudinal slideway upon which said drill tube and drive head are mounted for longitudinal sliding movement in common, said drive head having a sprocket wheel drive member; an endless elongate sprocket chain having guide wheels anchored at the upper and lower ends of the slideway, one reach of said endless chain engaging said sprocket wheel drive member to form a traveling drive connection between the drive head and the endless chain, whereby transmission of rotary motion to said drive head also effects longitudinal thrust on said drill tube; and means for rotating said chain.

6. The combination. recited in claim 5, wherein a removable soil sample tube is disposed concentrically within said drill tube for receiving core samples cut by said drill tube, and a concentric control tube is fitted about said soil sample tube for telescopic movement relative thereto, the said soil sample tube and control tube passing through and beyond the drive head; wherein extendable core-keeper means are disposed at the core-receiving end of said soil sample tube for operation by the telescoping action of said control tube; and wherein manually-operable means are provided for telescoping said control tube relative to said soil sample tube for extending said core-keeper means to secure soil cores therein for removal with said soil sample tube.

'7. The combination recited in claim 6, wherein a clamping ring normally interlocks the control tube and the soil sample tube as an operative unit; wherein the manually-operable telescoping means comprises a cap fitting about the upper end of the soil sample tube in engagement with the control tube, and a handle connected to said cap and arranged so that downward pressure may be manually applied to said cap for telescoping the control tube downwardly relative to said soil sample tube when the said clamping ring is released; wherein a resilient latching assembly normally engages said handle and exerts downward pressure thereon; and wherein rigid pressure-absorbing means normally engage said clamping ring and prevent the said downward pressure of said latching assembly from being imparted to the control tube.

8. The combination recited in claim '7, wherein the pressure-absorbing means are stepped risers, and the clamping ring is provided with outwardly projecting pins which normally engage lower steps of the respective risers, whereby core compaction is visibly and audibly indicated by rising of said clamping ring and the pins thereof on said stepped risers.

9. The combination recited in claim 8, wherein the stepped risers and resilient latching assembly are fixed to a base plate which is mounted on the drill tube drive head and through which the control tube and soil sample tube extend; wherein the handle is pivotally linked to a standard which is fixed to said base plate in spaced opposition to said resilient latching assembly, the two being disposed at opposite sides of said tubes; and wherein the cap is pivotally suspended from sand handle above said tubes.

10. The combination recited in claim 9, wherein the soil sample tube is split longitudinally so it may be opened to release core samples contained thereby.

11. The combination recited in claim 10, wherein the soil sample tube has an external collar at its lower end which is longitudinally slotted at intervals about its inner circumference; and wherein the core-keeper means comprise arouately-formed resilient fingers disposed within the respective slots, the control tube terminating sufficiently short of said collar in its normal position to provide retracted positioning for said fingers, downward telescoping movement of said control tube serving to push said fingers into extended core-retaining position.

12. The combination recited in claim 5, wherein the traveling drive connection comprises a sprocket and brake drum combination, the chain drive engaging said sprocket; and wherein a manually-operable brakev is arranged to enga e the. saidbrake drum and apply resistanceto rotation of said sprocket.

13. The combination recited in claim 5, wherein the drill end of the drill tube passes through a. guide roller assembly afiixed to the slideway, the. guide rollers of said assembly having their rotative'axes extending parallel to the drill tube so said rollers rotate with the rotation of said drill tuber l 14. The combination recited in claim 5, wherein a removable soil' sample tube is disposed concentrically within said drill tube for receiving core samples cut by said drill tube; and wherein an axial-pressure reacting assembly caps the said soil sample tube for indicating the occurrence of core compaction.

15. The combination recited in claim 5, wherein the slideway is pivoted at the rear of a trailer unit which is equipped with a tongue hitch and a pair of road wheels, the slideway and drill tube assembly being adapted to ride in a reclining position on said trailer unit during travel and to be tilted upright for drilling purposes; and wherein the means for actuating the chain drive include an engine and a power transmission mounted forwardly on said trailer unit, the said drill tube assembly being adapted to slide into a position substantially counterbalancing the weight of said engine and power transmission so the tongue may be easily hitched to a road vehicle.

16. The combination recited in claim 5, wherein the slideway is pivoted intermediate its length on a vehicle for tilting to various drilling positions between a substantially horizontal traveling position and substantially the vertical, and wherein means are provided for raising said slideway and the drill tube assembly to a desired drilling position.

17. A drill tube assembly for use in obtaining core samples of soil, comprising an external drill.

tube; a soil sample tube concentrically disposed Within said drill tube for receiving core samples of soil out by said drill tube, said soil sample tube having an. external collar at its drill end which is longitudinally slotted at intervals about the inner circumference thereof; arcuately formed and resilient fingers slidably disposed within the respective slots of said collar; a control tube snugly and concentrically fitted about said soil sample tube for telescopic movement relative thereto, said control tube terminating sufficiently short of said collar in. its normal position to provide retracted positioning for said fingers; and means for telescoping said control tube downwardly relative to said sample tube for pushing said fingers into core-retaining extended position.

18. In an earth drilling machine, a rotatable earth drill; drive means secured to said drill, said drive means including a rotary drive member; a slideway upon which said drill and said drive means are mounted for longitudinal sliding movement in common; and endless elongate chain drive having upper and lower chain guide wheels affixed to said slideway, thus extending the chain drive longitudinally of the slideway, so that one reach of said chain drive engaging said rotary drive member constitutes a traveling drive connection between said drive means and said chain drive, whereby transmission of rotary motion to said drive means also effects longitudinal thrust on said earth drill; and means for actuating said chain drive.

19. The combination recited in claim 18, wherein the rotary drive member of said drive means 15 ifsa sprocket wheel; and wherein a pair of idler sprocket wheels hold the said one reach of the chain drive in engagement with said drive sprocket wheel toform the said. traveling drive connection between the drive means and the chain drive.

JAMES A. HARDMAN.

References Cited in the file of this patent UNITED STATES PATENTS Nurnber Number 16 Name Date Moore Dec. 21, 1920 Gehrandt -1 Aug. 12, 1924 Conrey May 4, 1926 Oliver Apr. 12, 1927 Smith et al Nov. 8, 1932 Dodds Oct. 29, 1935 Thrift July 7, 1936 Johansen July 21, 1936 Drachman Jan. 26, 1943 Slater Nov. 20, 1945 

